1. Technical Field
The present disclosure relates generally to apparatus and methods for providing percutaneous access to an internal operative site during a surgical procedure and, more particularly, to apparatus and methods for creating a fluid-tight seal around an outer surface of a surgical instrument inserted therethrough, for reducing the amount of insertion force required to insert a surgical instrument therein and for delivering a medicament to the target delivery site.
2. Background of Related Art
Minimally invasive surgical procedures are performed throughout the body and generally rely on obtaining percutaneous access to an internal surgical site using small diameter tubes (typically 5 to 12 mm), usually referred to as trocars, which penetrate through the skin of the patient and open adjacent the desired surgical site. A viewing scope is introduced through one such trocar, and the surgeon operates using instruments introduced through other appropriately positioned trocars while viewing the operative site on a video monitor connected to the viewing scope. The surgeon is thus able to perform a wide variety of surgical procedures requiring only a few 5 to 12 mm punctures through the patient's skin, tissue, etc. adjacent the surgical site.
Certain minimally invasive surgical procedures are often named based on the type of viewing scope used to view the area of the body which is the operative site. For example, laparoscopic procedures use a laparoscope to view the operative site and are performed in the interior of the abdomen through a small incision. Such laparoscopic procedures typically require that a gas, such as carbon dioxide, be introduced into the abdominal cavity. This establishes pneumoperitoneum wherein the peritoneal cavity is sufficiently inflated for the insertion of trocars into the abdomen.
Pneumoperitoneum is established through the use of a special insufflation needle, called a Veress needle, which has a spring-loaded obturator that advances over the sharp tip of the needle as soon as the needle enters the abdominal cavity. This needle is inserted through the fascia and through the peritoneum. Generally, the surgeon relies on tactile senses to determine the proper placement of the needle by recognizing when the needle is inserted through the fascia and then through the peritoneum. After establishing pneumoperitoneum, the next step in laparoscopic surgery involves the insertion of a trocar, obturator or trocar/obturator assembly into the abdominal cavity.
Preferably, the trocars used in laparoscopic procedures should be readily sealable to inhibit the leakage of the insufflation gas from the abdominal cavity, in particular, should be designed to inhibit leakage from the region between the external periphery of the trocar and the abdominal wall.
In order to reduce the amount of insufflation gas which escapes from the abdominal cavity, a radially expandable access system has been developed to provide improved sealing about the periphery of the trocar. A system for performing such a function is commercially available from United States Surgical, a division of Tyco Healthcare, Ltd. under the trademark VERSAPORT™. Certain aspects of the expandable access system are described in commonly assigned U.S. Pat. Nos. 5,431,676; 5,814,058; 5,827,319; 6,080,174; 6,245,052 and 6,325,812, the entire contents of which are expressly incorporated herein by reference.
As disclosed therein, the expandable access system includes a sleeve having a sleeve body, typically made up of a radially expandable braid covered by an elastomeric layer. The braid initially has an inner diameter of about 2 mm and an outer diameter of about 3.5 mm. In use, passage of a surgical instrument (i.e., trocar, cannula, obturator, etc.) through the expandable access system causes radial expansion of the sleeve, typically to a final diameter of 5 mm, 10 mm or 12 mm. However, the sleeve can be expanded to any necessary diameter in order to accommodate the particular surgical instrument. The expandable access system further includes a handle affixed to a proximal end of the sleeve, the handle including a passage formed therein for the introduction of surgical instruments, through the handle, into the sleeve body.
A method of use of the expandable sealing apparatus includes inserting a pneumoperitoneum needle through the radially expandable sleeve body of the expandable access system to thereby form a needle/sleeve assembly. The needle/sleeve assembly is then introduced through the patient's abdomen by engaging the sharpened distal end of the pneumoperitoneum needle, protruding from the distal end of the sleeve body, against the body tissue of the body cavity and advancing the needle/sleeve assembly into the body cavity until the needle/sleeve assembly extends across the layers of the body tissue thereby forming an incision in the body tissue. The pneumoperitoneum needle is then removed from the body of the sleeve. A trocar, having a diameter smaller than the opening in the handle and larger than the lumen of the sleeve, is then introduced through the opening in the handle and into the abdomen of the patient. As a result, due to radial expansion of the sleeve by the trocar, the incision is subsequently also radially expanded. Trocars used in laparoscopic procedures include a valve at a proximal end thereof in order to permit passage of a viewing scope or other surgical instrument therethrough while simultaneously inhibiting escape of insufflation gas from the abdominal cavity.
Accordingly, in view of the need to maintain the atmospheric integrity of the abdominal cavity, a continuing need exists for a sealing assembly which reduces the escape of insufflation gas from the abdominal cavity and, more particularly from between the interface of the inner surface of the expandable access system and the outer surface of the surgical instrument (i.e., trocar).
In addition, a need exists for an access assembly which is capable of delivering a quantity of a medicament to a target surgical site. Still further, the need exists for an access system which requires a reduced insertion force for passing the cannula assembly through the expansion assembly.